Breast cancer is the leading cause of cancer in females of reproductive age. Young women may be affected by breast cancer even before motherhood. Current reproductive practices meant to delay childbearing, is also contributing to increasing breast cancer incidences in women, before their first pregnancy. In this context, a study reported that although more than half of the young women diagnosed with breast cancer were keen on having children, only 10% of them succeeded in becoming pregnant after treatment for breast cancer. Moreover, the study revealed that breast cancer survivors were least likely to have children among all cancer survivors.
Additionally, it has been a matter of great concern among researchers that pregnancy can cause recurrence of cancer in women, previously diagnosed with breast cancer. Hormone-sensitive breast cancer (estrogen receptor positive) was more likely to recur, since many cases of breast cancer progression is mediated by estrogen (a reproductive hormone). Moreover, pregnancy can interrupt the hormonal treatment for breast cancer, which can increase the risk of its recurrence.
Such concerns among the healthcare providers and patients now stands disproved, as a study found that women with estrogen receptor (ER) positive breast cancer, tends to become pregnant later than ER negative breast cancer. The study also found that almost a quarter of the patients with ER positive breast cancer became pregnant, even after five years following cancer diagnosis. The study was one of the largest case-control study conducted, which included 1,207 women with breast cancer. It was aimed at finding the safety of pregnancy, after a diagnosis of breast cancer, specifically ER positive cancers. More than 50% of the included subjects had ER positive breast cancer with unfavorable prognostic factors.
With a median 10-year’ follow-up of patients, it was observed that 333 women became pregnant and ER positive breast cancer patients were able to achieve pregnancy later in their lives. There was no significant difference in disease-free survival among women who became pregnant, when compared to women who were not pregnant. Similarly, the overall survival rates did not also differ between these two groups. An interesting finding is that ER negative breast cancer women had a 42% less chance of mortality, as compared to women who did not become pregnant.
Primary investigator of the study Matteo Lambertini, a medical oncologist at the Institut Jules Bordet in Belgium said that “Our findings confirm that pregnancy after breast cancer should not be discouraged, even for women with ER-positive cancer”. He also mentioned that “However, when deciding how long to wait before becoming pregnant, patients and doctors should consider each woman’s personal risk for recurrence, particularly for women who need adjuvant hormone therapy.” Although the study brings out certain important points, further research is needed to fully understand the effect of pregnancy on other associated factors, such as HER2 status, BRCA mutation, breast feeding, and hormonal therapy.
1. Pregnancy After Breast Cancer Does Not Increase Chance of Recurrence [Internet]. ASCO. 2017 [cited 2017 Jun 24]. Available from: http://www.asco.org/about-asco/press-center/news-releases/pregnancy-after-breast-cancer-does-not-increase-chance
2. Letourneau JM, Ebbel EE, Katz PP, Katz A, Ai WZ, Chien AJ, et al. Pretreatment fertility counseling and fertility preservation improve quality of life in reproductive age women with cancer. Cancer. 2012 Mar 15;118(6):1710–7.